Drawing implement.



F. A. ALTENEDER.

DRAWING IMPLEMENT.

APPLICATION FILED MAY 3. 19l'6.

m Patented Apr. 3,1917.

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IEEILIJINAND A. ALTENEIDER, 0F GLENSIDE, PENNSYLVANIA.

DRAWING IMPLEMENT.

Specification of Letters Patent.

Patented Apr. 3, I917.

Application filed May 3, 1916. Seria1 No. 95,283.

To all whom it may concern.

Be it known that I, FERDINAND A. AL- TENEDER, a citizen of the UnitedStates, residing at Glenside, in the State of Pennsylvania, haveinvented a certain new and useful Improvement in Drawing Implements,whereof the following is a specification, reference being had to theaccompanying drawings. I

My invention relates to implements of the class including T-squares,triangles, ship and railway curves, irregular scrolls, etc., formed ofcelluloid or other translucent or transparent material having an edge ofstraight or curved contour adapted to serve as a guide for a pencil orpen point in linear drawing, and is an improvement upon my inventiondescribed in Letters Patent of the United States No. 697,594 dated April15, 1902 wherein I disclose such an implement having the entire extentof its guiding edges rendered opaque by channeling or recessing eachedge, throughout its length, and securing an opaque substance therein.Such channels may be readily formed by a broaching tool caused totraverse each edge from end to end thereof. However, in a triangle, orother implement where two such guidlng edges meet in acute angular orother transverse relation, the points thus formed (and which aresubjected to greater stresses in use than the other portions of theimplement,)

are relatively weaker than the rest of the implement so that the sidewalls of the channels at such points may readily be accidentally splitapart, for instance, if the implement is dropped upon such a point.Moreover, in said Letters Patent I showed channels having right angularcorners at their inner sides, but have since found that such cornerspermit the walls of the channels to be broken off under much less strainthan if the channels have no such corners but are rounded at their innersides.

- Therefore, it is the object and effect of my present invention toavoid the disadvantages aforesaid, and, accordingly, my presentinvention includes the provision of a channel in the guiding edge ofsuch an implement which terminates short of the ends of said edge;leaving the ends of said edge transparent and solidly homogeneous andtherefore capable of resisting such stresses as would split the ends ofthe prior structure. Moreover, I prefer to employ a rotary cutter informing such a channel so as to leave the channel tapering, in an arcualcurve, at each end, from its inner to its outer side.

My invention includes the various novel features of construction andarrangement hereinafter more definitely specified.

In said drawing; Figure I is a plan view of a triangle embodying myinvention.

Fig. II is a fragmentary sectional. view taken on the line II in Fig. I.

Fig. III is a sectional view similar to Fig. II but showing modifiedmeans for rendering the guiding edge opaque.

Fig. IV is a fragmentary perspective view of the upper point of thetriangle shown in the latter to pressure, as by dropping or striking it.

.In said figures; 1 is the implement body of transparent material havingopposite plane faces 2 and 3 with the guiding edge or edges 4. Saidguiding edges are rendered opaque to the extent indicated in Fig. I byany convenient means attached to said body 1.

In the form of my invention shown in Fig. II; said body 1 has the openchannel or recess 5 extending betwen said plane surfaces 2 and 3,parallel therewith and also parallel with said guiding edge 4:. Saidrecess being coated with a layer of black varnish 6, the effect is torender said guiding edge lopaque to the extent of said recess. In theform of my invention shown in Fig. III the recess 5 is filled with anopaque substance 7, which presents a solid front along the edge 4-. Ineither case, as said recesses 5 terminate short of each end of each ofsaid edges 4, said body 1 is notonly solidly homogeneous at the ends ofsaid edges, as best shown in Fig. IV, but said ends are transparent, asindicated in Fig. I, so that lines upon the surface of the drawing,approximating said edge, may be observed through the latter, at saidends.

Although such channels or recesses 5 may be formed in any convenientmanner, provided that they terminate short of the ends of the edges 4:,as above described; I prefer to form them with a rotary cutter havingarounded edge of the configuration of said channels outlined in Figs. IIand HI; whereby said channels are not only left taporing, in an arcualcurve, at each end, from their inner to their outer sides, as indicatedin Fig. I, but their inner sides are rounded so as to avoid the sharpcorners 8 characteristic of the structure illustrated in my Let- Copiesof this patent may be obtained for ters Patent aforesaid and which isshown in Fig. V in this case. Of course, terminating said channels shortof the ends of the edges 1-, (whether rounded at their inner sides ornot) precludes such deformation as abore contemplated with reference tothe prior structure, which is indicated in Fig. V; wherein the points 9of the implement body 10, primarily divided by the channels 11 extendingto the ends thereof, have been separated and deformed by dropping theimplement upon the point shown.

Implements constructed as above described, possess all of the advantagesof those which are transparent throughout their breadth in'enabling thedraftsman to observe drawings through them,-the opaque edges,contrasting sharply with the drawing surface, facilitating theadjustment of the implements to the existing lines of the drawings.Although such adjustment was facilitated by the construction andarrangement shown in my Letters Patent aforesaid, the presentimprovement affords the advantages of not only leaving the implementmore durable at its points but of permitting observation of the drawingthrou h the points and thus facilitating adjustment of the latter tomarks upon the drawings.

Although I prefer to form such implements of material which is not onlytranslucent but flexible, as celluloid or similar compounds, I do notdesire to limit myself to such material. Moreover, I do not desire tolimit myself to the precise form or method of construction of myinvention herein set forth as it is obvious that various mod1ficationsmay be made therein without departopaque substance secured in saidchannel;

7 whereby said body is solidly homogeneous at the ends of said edge, andsaid edge is transparent at its ends and opaque intermediate thereof,throughout the extent of said channel.

2. An implement of the class described, comprising a body of transparentmaterial ha ing opposite parallel plane surfaces with guiding edge andhaving a longitudinal channel extending parallel with said edge andintermediate of said plane surfaces, but terminating short of each endthereof; said recess tapering, in an arcual curve, at each end, from itsinner to its outer side; and an ing a guiding edge and a recess in saidguiding edge, terminating short of each end thereof; and an opaquesubstance secured in said recess.

An implement of the class described, comprising a transparent bodyhaving a guiding edge and a recess in said guiding edge, terminatingshort of each end thereof, and tapered at each end, and an opaquesubstance secured in said recess.

6. An implement of the class described, comprising a transparent bodyhaving a guiding edge and a recess in said guidiiw edge, terminatingshort of each end thereof; and an opaque .substance secured in saidrecess.

7. An implement of the class described, comprising a transparent bodyhaving a guiding edge, of uniform thickness which is transparent at itsends but opaque intermediate of said ends.

In testimony whereof, I have hereunto signed my name at Philadelphia,Pennsyl- Vania, this twentieth day of April, 1916.

FERDINAND A. ALTENEDER.

Witnesses:

ARTHUR E. PAIGE, ANNA ISRAELVITZ.

five cents each, by addressing the Commissioner of Patents, Washington,I). C.

